1. Technical Field
The present invention relates to a flat panel display device, and more particularly, to a flat panel display device in which films having various functions are formed using a liquid coating method, the various functions of the films including improving screen contrast and color sense, and preventing external light reflection.
2. Related Art
A flat panel display device refers to a display device that includes a thin display panel to realize a thin profile. This is in contrast to the cathode ray tube that has a substantial depth. Flat panel display devices can include the field emission display (FED) and the plasma display panel (PDP).
Such flat panel display devices include a black film to improve contrast. In the case where a luminosity factor is high at particular wavelengths, a compensation film that selectively absorbs these wavelengths to improve color sense is provided. Also, the flat panel display device includes an anti-reflection film so that shading of the screen does not occur as a result of external light.
Further, in the case of some plasma display panels, ultraviolet rays that pose a health risk are emitted, as are near infrared rays that cause the inadvertent operation of various electronic devices controlled by remote controllers. Therefore, films that shield the electromagnetic waves, ultraviolet waves, and near infrared rays are needed.
As a result, the flat panel display device provides a filter to an external surface of a front substrate to accomplish the above-described objects of improving contrast and color sense, preventing external light reflection, and blocking electromagnetic waves, ultraviolet waves, and near infrared rays in the case of the plasma display panel. The above-described filter is formed by selecting various films that accomplish these described objects, providing those various films onto a transparent baseplate (e.g., a glass or acryl plate), and then adhering the films to the baseplate. A hot pressing process is typically performed to attach the films.
In the hot pressing process, an adhesive layer is provided between the baseplate and film, and these elements are heated at a high temperature and in a high pressure state to thereby attach the film to the baseplate. As a result, expensive coating films must be used in the hot pressing process. Also, an increase in the number of films results in a corresponding increase in the number of adhesive layers and hot pressing processes that need to be performed.
In addition, in the case where the flat panel display device is made to a large size and requires very strict arrangement conditions, various problems result after the films are attached even with slight variations in the film setting. The film of the extreme outer layer that is attached using the hot pressing process may generate stress from being thermally deformed. If this occurs, a surface of the film is deformed by the stress, and minute cracks are generated on the film surface to thereby reduce the levelness of the screen.
Hence, manufacture of the flat panel display device including a filter made through the hot pressing process as described above results in a reduction in productivity, an increase in production costs, and a low filter quality. Further, surface hardness of the coating films applied to the filter is low such that scratches easily occur. This makes the product less attractive and reduces the lifespan of the device.